1. Field of the Invention:
The present invention relates vehicle suspension systems and more particularly to the assembly of the suspension for a steering axle installed at the front end of a vehicle such as a truck.
2. Description of the Prior Art:
A common type of front end suspension for a truck steering axle relies on leaf springs positioned adjacent to and above opposed ends of the steering axle to locally support the weight of the truck from the axle. The leaf springs are elongated, flexible bars mounted perpendicular to the axle and parallel to the to major frame side rails of the vehicle chassis. Each leaf spring is rigidly attached at approximately its center point to the steering axle. Opposite ends of each leaf spring are coupled to a frame side rail fore and aft of the axle, helping to align and locate the axle. Shock absorbers are attached between the frame side rails and each end of the axle to dampen motion.
The assembly of front end suspensions requires the inclusion of components which: allow for the attachment of the shock absorber between the vehicle chassis and the axle; establish the proper spacing between the leaf spring and the axle to place the vehicle at its proper height; and, insure the proper alignment of the suspension and steering components. A factor complicating front end suspension assembly is that leaf springs of different sizes are used depending upon the anticipated use of the truck. Typically, leaf springs having a width of 3xe2x80x3 (7.6 cm) are used for medium duty applications while leaf springs having a width of 4xe2x80x3 (10.2 cm) are used for heavy duty applications. The differences in spring widths have prevented the use of a single element spacer in front end suspensions which meets the need to position the vehicle, insure proper alignment of the components for steering and provide a connection point for a shock absorber. While single piece devices exist which provide for one spring width, none is known to the inventors which works with springs of different widths.
A single piece device providing spacing, alignment and shock absorber installation to both common leaf spring widths would simplify manufacture. Such an element should also be easy to install correctly during vehicle assembly. What is needed is a unitary spacer, connector and alignment element which simplifies manufacture and reduces the number of parts to be kept in inventory.
The invention provides a vehicle suspension subassembly for a steering axle having a reduced number of parts and exhibiting interchangeability among leaf springs of differing sizes. The leaf springs at each end of a steering axle have mounting pads. The steering axle has horizontally disposed mounting pads adjacent to each end for cooperation with the leaf spring mounting pads. A spacing element disposed between mounting pad and the leaf spring has top and bottom major surfaces for mating with the leaf spring mounting pad and the steering axle mounting pad. The outside vertical sides of the spacing element are shaped to fit snugly against U-bolts of differing sizes used with leaf springs of different widths. The top and bottom major surfaces of the spacing element are canted with respect to one another to set steering axle caster. A shock absorber mount extends from the spacing element.
Additional effects, features and advantages will be apparent in the written description that follows.